Heaters which are comprised of several heat exchange units are well known to the prior art. However, these heaters are usually complicated, inefficient, and expensive. Many of them generate noxious fumes, some of which are vented to the atmosphere.
It is an object of this invention to provide a heater whose operation does not create a substantial amount of pressure in the system.
It is another object of this invention to provide a heater which will not generate any fumes.
It is yet another object of this invention to provide a heater which is relatively safe, shielding the user from hot surfaces therein.
It is yet another object of this invention to provide a heater which is relatively efficient.
It is yet another object of this invention to provide a heater which is relatively inexpensive.
It is yet another object of this invention to provide a heater whose output can readily be varied.